Purpose; Investigating the effects of unequal sub-arc personalized collimator angle selection on the quality of Volumetric Modulated Arc Therapy (VMAT) plans for treating multiple brain metastases. Methods: This study included 21 patients, each with 2-4 target volumes of multiple brain metastases. Two stereotactic radiotherapy (SRT) approaches were utilized: sub-arc collimator VMAT (SAC-VMAT) and fixed collimator VMAT (FC-VMAT). In the SAC-VMAT group, multi-leaf collimators (MLC) shaped the target area, dividing the full arc into four unequal sub-arcs under the beam's eye view (BEV). Each sub-...
